The increasing demand for wireless telecommunication services has resulted in the growth of many wireless telecommunication systems and increase in the number of roaming wireless subscribers. With the third generation (3G) systems, efforts have been implemented to accommodate and distribute the increased traffic load in the network among a number of mobile switching centers being arranged to form a mobile switching center pool (MSC pool) for handling communications such as mobile terminated calls (MTC) towards a mobile station or mobile originated calls (MOC) from the mobile station. Usually, the MSCs form an interface towards a core network (CN), wherein the communications towards the mobile station are handled via a radio access network which may comprise a node B or a radio network controller (RNC) or a base station controller (BSC).
By way of example, in order to set up a MTC, a MSC in which the mobile station is registered is determined by a Home Location Register (HLR). The MSC initiates a paging request towards the mobile station, which, in response thereto, sends a paging response towards the MSC to proceed further with the MTC. However, if the MSC in which the mobile station is registered is out of service then the RNC may route the returned paging response to any MSC in MSC pool. However, the attempt to establish the MTC may fail if the paging response is transmitted to a MSC which has not been involved in establishing the MTC.
Accordingly, there exists a need for efficiently managing mobile terminated calls in particular if one of the MSCs in the MSC pool is out of service.